1. Field of the Invention
The invention relates to devices for preventing propellers attached to motors from being stolen. More particularly, the present invention relates to locking devices for locking marine propellers to the motors to which the propellers are connected when the motors are not in use to prevent unauthorized removal of the propellers.
2. Description of the Related Art
Theft of propellers from outboard marine engines and from marine outdrives has long been a problem for boat owners. Marine propellers are now widely available in stainless steel and are much more expensive than standard aluminum propellers and are much more likely to be stolen than standard aluminum propellers. An inexpensive locking device capable of being quickly attached to a propeller has long been needed to prevent such theft of increasingly expensive marine propellers.
As in known in the art, marine propellers on conventional outboard motors and inboard-outdrive units are commonly attached by a common internally threaded nut having a hexagonal outer surface to the threaded outer end of a splined drive shaft extending from a gear housing on the lower end of the outboard motor or inboard-outdrive through the propeller. A person desiring to steal a propeller need only remove the nut holding the propeller on the drive shaft, and slide the propeller off of the splines on the drive shaft.
Devices for preventing unauthorized removal of marine propellers are known in the art. Exemplary of the Patents of the related art are the following U.S. Pat. Nos. 5,246,345; 5,184,488; 4,697,444; and 3,981,617; and in East German Patent 136,595.